Kwangwon Rhee

Efficacy of a Metallic Stent Covered with a Paclitaxel-Incorporated Membrane Versus a Covered Metal Stent for Malignant Biliary Obstruction: A Prospective Comparative Study

BackgroundThe placement of a self-expandable metallic stent (SEMS) is a widely used nonsurgical treatment method in patients with unresectable malignant biliary obstructions but SEMS is susceptible to occlusion by tumor ingrowth or overgrowth.AimThe efficacy and safety of a metallic stent covered with a paclitaxel-incorporated membrane (MSCPM) in which paclitaxel provided an antitumoral effect was compared prospectively with those of a covered metal stent (CMS) in patients with malignant biliary obstructions.MethodsPatients with unresectable distal malignant biliary obstructions (nxa0=xa0106) were prospectively enrolled in this study at multiple treatment centers. A MSCPM was inserted endoscopically in 60 patients, and a CMS was inserted in 46 patients. Patients underwent systemic chemotherapy regimens alternatively according to disease characteristics.ResultsThe two groups did not differ significantly in mean age, male to female ratio, or mean follow-up period. Stent occlusion due to tumor ingrowth occurred in 12 patients who received MSCPMs and in eight patients who received CMSs. Stent patency and survival time did not differ significantly between the two groups (pxa0=xa00.116, 0.981). Chemotherapy had no influence on stent patency, but gemcitabine-based chemotherapy was a significant prognostic factor for survival time (pxa0=xa00.012). Complications, including cholangitis and pancreatitis, were found to be acceptable in both groups.ConclusionsAlthough the use of a MSCPM produced no significant differences in stent patency or patient survival in patients with malignant biliary obstructions compared with the use of a CMS, this study demonstrated that MSCPM can be used safely in humans.

Recanalization of refractory benign biliary stricture using magnetic compression anastomosis

BACKGROUND AND STUDY AIMSnEndoscopic or percutaneous treatments are preferentially attempted for benign biliary stricture (BBS). However, these methods are not feasible if a guide wire cannot be passed through the stricture. This study evaluated the usefulness and technical requirements of magnetic compression anastomosis (MCA) in refractory BBS.nnnPATIENTS AND METHODSnMCA was performed in patients with BBS that had not been resolved with conventional treatments. One magnet was delivered through the percutaneous transhepatic biliary drainage tract and the other magnet was advanced through three different routes. After magnet approximation and recanalization, an internal drainage catheter was placed for 6 months and then removed.nnnRESULTSnSeven patients underwent MCA, and recanalization was successfully achieved in five. MCA failure in two cases was attributed to long stenotic segments and parallel alignment of the axes of the magnets. The mean follow-up period after recanalization was 485.2 days. Five patients with successful recanalization showed no MCA-related complications or restenosis.nnnCONCLUSIONSnMCA represents an alternative nonsurgical method of BBS recanalization that cannot be treated with conventional methods.

Undifferentiated early gastric cancer diagnosed as differentiated histology based on forceps biopsy

Histological diagnosis before endoscopic resection (ER) is important to determine whether ER should be performed; indeed, the use of ER for undifferentiated early gastric cancer (UD-EGC) remains controversial. The aim was to investigate the clinicopathological features of UD-EGC in ER specimens, diagnosed as differentiated histology based on biopsy. 289 patients with EGC were treated by ER. Among them, 13.1% were diagnosed as UD-EGC after ER, and 18.4% of them showed differentiated histology based on biopsy before ER. We analyzed UD-EGC with differentiated histology (D-group) compared to undifferentiated histology (UD-group) on biopsy. The D-group showed moderately differentiated adenocarcinoma on biopsy and poorly differentiated adenocarcinoma in ER specimens. The D-group was significantly associated with older age, intestinal metaplasia in the surrounding mucosa, and larger size than the UD-group. Gland portion of tumor, mixed-type Lauren classification, submucosal invasion, lymphovascular invasion, and perineural invasion were more common in the D-group than in the UD-group. The number of biopsies was not different between the groups. When comparing the histopathological mapping findings and endoscopic appearances of the D-group, the zone of transition from differentiated to undifferentiated histology was frequently found on one or two peripheral sides of the lesion. In conclusion, areas of EGC greater than 20mm with moderately differentiated histology on biopsy may contain an undifferentiated component. UD-EGC with differentiated histology on biopsy may show more aggressive behavior than UD-EGC, consistent with the biopsy pathology. Biopsy at several peripheral sides of the lesion may be helpful for diagnosis of UD histology before treatment.

For patients with primary achalasia the clinical success of pneumatic balloon dilatation can be predicted from the residual fraction of radionuclide during esophageal transit scintigraphy.

BackgroundEsophageal transit scintigraphy (ETS) and esophagography have long been used to evaluate patients with achalasia. The objectives of our study were to evaluate the efficacy of endoscopic pneumatic dilatation (EPD) as treatment for Koreans with achalasia and to determine which findings from ETS and esophagography predict successful treatment of achalasia.MethodsPatients with achalasia who were treated by EPD between April 2002 and January 2012 were recruited. We defined the success of EPD as 6xa0months or more of clinical remission without symptoms or a decrease in the Eckardt scores by at least two points and a total Eckardt score not exceeding 3. We reviewed the percentage of maximum scintigraphic activity retained in the esophagus at 30xa0s (R30) and the post-PD rate of reduction of R30 ((Pre R30xa0−xa0Post R30)/Pre R30xa0×xa0100) by ETS. Possible predictive factors determined by ETS and esophagography were analyzed.ResultsOur study included 53 eligible patients. The median symptom score (Eckardt score) was 5 (4–8). R30 and T1/2 were, respectively, 61.8xa0% and 38.5xa0min before EPD and 20xa0% and 4.19xa0min after EPD. Successful EPD was achieved for 40 of 53 (75.47xa0%) patients. Age (≥40, pxa0=xa00.027) and post-PD rate of reduction of R30 (>20xa0%, pxa0=xa00.003) were best prognostic indicators of clinical success. There were no perforations related to EPD.ConclusionOlder age and a post-PD rate of reduction of R30 were strongly associated with better outcomes. Examination with ETS before and after EPD can be used to objectively assess a patient’s short-term response to EPD.

Self‐expandable metal stents for malignant esophageal obstruction: a comparative study between extrinsic and intrinsic compression

Self-expandable metal stents (SEMSs) are effective for malignant esophageal obstruction, but usefulness of SEMSs in extrinsic lesions is yet to be elucidated. This study is aimed at evaluating the clinical usefulness of SEMSs in the extrinsic compression compared with intrinsic. A retrospective review was conducted for 105 patients (intrinsic, 85; extrinsic, 20) with malignant esophageal obstruction who underwent endoscopic SEMSs placement. Technical and clinical success rates were evaluated and clinical outcomes were compared between extrinsic and intrinsic group. Extrinsic group was mostly pulmonary origin. Overall technical and clinical success rate was 100% and 91%, respectively, without immediate complications. Extrinsic and intrinsic group did not differ significantly in clinical success rate. The median stent patency time was 131.3 ± 85.8 days in intrinsic group while that of extrinsic was 54.6 ± 45.1 due to shorter survival after stent insertion. The 4-, 8-, and 12-week patency rates were 90.5%, 78.8%, and 64.9% respectively in intrinsic group, while stents of extrinsic group remained patent until death. Uncovered, fully covered, and double-layered stent were used evenly and the types did not influence patency in both groups. In conclusion, esophageal SEMSs can safely and effectively be used for malignant extrinsic compression as well as intrinsic.

Endoscopic Treatment of Pancreatic Calculi

Chronic pancreatitis is a progressive inflammatory disease that destroys pancreatic parenchyma and alters ductal stricture, leading to ductal destruction and abdominal pain. Pancreatic duct stones (PDSs) are a common complication of chronic pancreatitis that requires treatment to relieve abdominal pain and improve pancreas function. Endoscopic therapy, extracorporeal shock wave lithotripsy (ESWL), and surgery are treatment modalities of PDSs, although lingering controversies have hindered a consensus recommendation. Many comparative studies have reported that surgery is the superior treatment because of reduced duration and frequency of hospitalization, cost, pain relief, and reintervention, while endoscopic therapy is effective and less invasive but cannot be used in all patients. Surgery is the treatment of choice when endoscopic therapy has failed, malignancy is suspected, or duodenal stricture is present. However, in patients with the appropriate indications or at high-risk for surgery, endoscopic therapy in combination with ESWL can be considered a first-line treatment. We expect that the development of advanced endoscopic techniques and equipment will expand the role of endoscopic treatment in PDS removal.

An Evidence of Esophageal Decompensation in Patients With Achalasia in the View of Its Subtype: A Retrospective Study

Background/Aims Achalasia is a primary motility disorder of esophagus. Many parameters represent esophageal function and morphologic changes, but their interrelationship is not yet established. We hypothesized that esophageal body would need to generate unusual pressure to empty the food bolus through the non-relaxing lower esophageal sphincter in patients with achalasia; therefore, higher is the residual lower esophageal sphincter pressure, greater would be the contraction pressure in the esophageal body in these patients. To verify the hypothesis, correlations among parameters from esophageal manometry, esophagography and esophageal transit study had been investigated. Methods A retrospective review of 34 patients was conducted. Resting lower esophageal sphincter pressure and contraction pressure of esophageal body were obtained from conventional esophageal manometry. Diameter of esophageal body was measured from barium column under esophagography. Radionuclide imaging was performed to assess the esophageal transit, designated as R30, which was the residual radioactivity at 30 seconds after ingesting radioactive isotope. Results In vigorous achalasia group, contraction pressure of esophageal body was negatively correlated to dilated diameter of esophageal body (P = 0.025, correlation coefficient = -0.596). Esophageal transit was more delayed as dimensions of esophageal body increased in classic achalasia group (P = 0.039, correlation coefficient = 0.627). Conclusions Diameter of esophageal body in classic achalasia was relatively wider than that of vigorous achalasia group and the degree of delayed esophageal transit was proportionate to the luminal widening. Patients with vigorous achalasia had narrower esophageal lumen and relatively shorter transit time than that of classic achalasia group. Proper peristalsis is not present in achalasia patients but remaining neuromuscular activity in vigorous achalasia patients might have caused the luminal narrowing and shorter transit time.

Impact of peritoneal carcinomatosis on clinical outcomes of patients receiving self-expandable metal stents for malignant colorectal obstruction

BACKGROUNDnPeritoneal carcinomatosis can influence clinical outcomes of patients receiving self-expandable metal stents (SEMS) for malignant colorectal obstruction, but data regarding this issue are sparse. We analyzed the clinical outcomes of post-SEMS insertion for malignant colorectal obstruction based on carcinomatosis status.nnnMETHODSnStent- and patient-related clinical outcomes were compared for carcinomatosis status in a retrospective review involving 323 consecutive patients (colorectal cancer 198 patients; extracolonic malignancy 125 patients) who underwent palliative SEMS placement for malignant colorectal obstruction from January 2005 to March 2012.u200aSeverity of carcinomatosis was classified as mild, moderate, or severe.nnnRESULTSnCarcinomatosis was observed in 190 patients (58.8u200a%). The rates of technical (84.7 vs. 94.7u200a%; Pu200a=u200a0.005) and clinical (73.2 vs. 83.5u200a%; Pu200a=u200a0.03) success were lower in patients with vs. without carcinomatosis. Rates of early (2.1u200a% vs. 3.0u200a%; Pu200a=u200a0.72) and delayed (1.6u200a% vs. 6.0u200a%; Pu200a=u200a0.08) perforation and stent failure (27.9u200a% vs. 26.3u200a%; Pu200a=u200a0.75) showed no difference. Technical and clinical success rates were significantly different based on the severity of carcinomatosis (technical success rate: mild 90.7u200a%, moderate 97.4u200a%, severe 76.3u200a%, Pu200a=u200a0.003; clinical success rate: mild 83.3u200a%, moderate 82.1u200a%, severe 63.9u200a%, Pu200a=u200a0.01). In multivariate analysis, severe carcinomatosis was identified as an independent factor related to technical (odds ratio [OR] 0.18, 95u200a% confidence interval [CI] 0.06u200a-u200a0.56) and clinical (OR 0.33, 95u200a%CI 0.15u200a-u200a0.74) success.nnnCONCLUSIONSnPeritoneal carcinomatosis was associated with decreased technical and clinical success rates in patients receiving SEMS for malignant colorectal obstruction. Moreover, the presence of severe carcinomatosis was an independent factor determining these clinical outcomes.